Coast battery swap

Flashlight Modding and DIY Parts
1

I have 3 coast lights (g50, g45, poly steel 400). Both g series use the 3 x aaa cartridge while the polysteele uses 4 x aaa.
I’d like to replace the batteries with the USB C rechargeable battery. I was wondering if a 18500 would fit or are there any other options?

PS I can take some pics and measurements if that helps?

2

Depends on how the batteries are configured in the lights.
If your 3xAAA has a battery holder like the one below, an 18650 should be easy to replace it since the voltage is essentially the same.
Doing a swap for 4xAAA might work depending on how the driver is setup and how the batteries are configured in the light.
Pics would help.
All the best,
Jeff

3

Have a couple cheap lights that use 3AAA and use 18500 with a rubber band wrapped around it to center the battery. The 18500 is non protected/no charger chip onboard.
Works well with great runtime.

HTH
Keith